1. Field of the Invention
The present invention relates to a multilayered absorbent hygiene product. More particularly, it relates to a stacked or layered product containing individual absorbent pads which are releasably attached one to another.
2. Description of the Prior Art
Absorbent products have long been used as feminine hygiene products. Discretion in the use of these products has been a goal of manufacturers and users alike. Absorbent pads and napkins used for feminine hygiene provide some specific capacity for absorbing body fluids. Once soiled, a product must be replaced by an unsoiled product. Unfortunately, a woman is not always at home or otherwise conveniently near a supply of these absorbent products, and it may be necessary for her to keep a minimal supply of products with her. Thus, feminine hygiene products have been manufactured to be carried conveniently in a woman's purse or pocketbook. These products have also been manufactured in convenient, individual packages to keep the product clean until use. However, more discrete ways to keep a ready supply of feminine hygiene products handy are constantly sought.
U.S. Pat. No. 2,929,379 to Poulsen suggested that a woman might carry a supply of three sanitary napkins in a sanitary napkin product having multiple layers. Aside from the multiple layers of absorbent pads which made up the sanitary napkin product, it incorporated cloth tabs which extended from the front and rear of the absorbent pad which were secured to a belt. This belt was separately worn about the user's waist. The use of the belt in conjunction with sanitary napkins allowed the napkins to be held closely to the user's body. The plurality of absorbent layers of the Poulsen product are stacked and attached in one general location proximate the front of the sanitary napkin product. The back of the upper individual layers was not anchored to the adjacent layer. It was constrained only by the nature of the belted product.
In more recent times, belted feminine hygiene products have generally been replaced by products which are releasably secured to a user's undergarments by means of a layer or strip of pressure sensitive adhesive disposed upon a garment-facing surface of the product. In addition, new and thinner products, including thin sanitary napkins and panty liners, have been developed. Panty liners may be used for applications other than those for which traditional sanitary napkins were designed. These feminine hygiene products are substantially thinner than conventional sanitary napkins and have a substantially concentrated absorbent volume. Thin feminine hygiene products therefore, have less of the absorbent fluff layer which helps to provide flexibility to the product.
Most feminine hygiene products have a body-facing absorbent side and a garment-facing barrier side. One or more lines of a pressure-sensitive adhesive are generally disposed on the garment-facing side to provide attachment means to removably affix the product to the garment. This pressure-sensitive adhesive is protected from contamination until use with a piece of release liner. When the product is to be used, the user must first remove the release liner and dispose of it. The disposal of a piece of release liner with each panty liner increases the waste generated by the use of these products. Thus, it is desirable to reduce the amount of release liner used in conjunction with panty liners in an era of increased environmental awareness.
Absorbent products have a finite absorbent capacity, and they must be periodically replaced. Manufacturers continue to search for products which are easily carried by a user, and which are convenient and discrete. One solution is discussed in U.S. Pat. No. 5,910,137 to Clark et al., which discloses a panty liner product having three single layers stacked and secured together. The bottom panty liner has a conventional adhesive disposed for positioning the product in the crotch area of a user's undergarment. Each remaining layer is releasably attached to the layer below it in the stack by adhesive or embossing (heat sealing) means. This illustrates that the adhesive is to be applied in two relatively small areas proximate the front and rear ends of the layer, or adjacent layers may be embossed at four discrete positions of the layers.
Additionally, Clark et al. also discloses a multilayered sanitary napkin product having smaller pads stacked on top of larger pads and secured with two discrete strips of adhesive tape. Again, these strips are at the ends of the pad layers.
After a substantial amount of research into the problems associated in developing panty liners having several removable absorbent layers, it has been discovered that panty liners having only one local attachment point between individual layers are susceptible to substantial movement of the unsecured portions of the panty liner layers. The forces acting on such pads tend to displace at least the topmost pad as the user moves. The displacement allows the pad to intrude into the area between the buttocks where it can be wedged, causing discomfort and painful chafing. This movement presents a major problem for users of thinner panty liners. Merely adding a second minor spot of adhesive cannot guarantee a firm attachment of the topmost panty liner through intermediate panty liner layers to the user's undergarment.
Using two small areas of adhesive spaced apart at the ends of a panty liner pad presents an additional problem. The adhesive may effectively attach adjacent pads at the adhesive application sites, but the adhesive cannot always prevent separation of the pads away from the application sites. Thus, when the application sites are located at the panty liner pad ends, the center section of adjacent pads can separate, causing problems similar to those identified above. Finally, while it is important that the absorbent layers of the panty liner product be secured together, the final product should be flexible enough to generally conform to the user to reduce chafing and other irritation.
Therefore, a new and useful panty liner product is needed having a plurality of absorbent pads which are releasably attached together in a secure manner. It is desirable that the product be flexible and comfortable to wear.